The USL First Division begins its playoffs this weekend with four quarterfinal series. The top-seed Seattle Sounders face the expansion Carolina RailHawks. In other series, the No. 2 seed Portland Timbers meet the defending champion Vancouver Whitecaps. The Montreal Impact plays the Puerto Rico Islanders, while the Atlanta Silverbacks and Rochester Rhinos square off in a battle of No. 4 and No. 5 seeds. The second game of the Portland-Vancouver series will be televised Sunday at 8 pm ET on Fox Soccer Channel. Fans can also catch USL playoff action on usllive.com.